package app08;
import java.util.Scanner;

public class NumberDoubler{
    public static void main(String[] args){
        Scanner scanner=new Scanner(System.in);
        String input=scanner.next();
        try{
            double number=Double.parseDouble(input);
            System.out.printf("Result:%s",number);
        }catch(NumberFormatException e){
            System.out.println("Invalid input.");
        }
        scanner.close();
    }
}
